CN114426290A - Sodium-free Fe-ZSM-5 molecular sieve and synthesis method thereof - Google Patents

Sodium-free Fe-ZSM-5 molecular sieve and synthesis method thereof Download PDF

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CN114426290A
CN114426290A CN202011087484.XA CN202011087484A CN114426290A CN 114426290 A CN114426290 A CN 114426290A CN 202011087484 A CN202011087484 A CN 202011087484A CN 114426290 A CN114426290 A CN 114426290A
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molecular sieve
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sodium
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CN114426290B (en
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王达锐
孙洪敏
刘威
金少青
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China Petroleum and Chemical Corp
Sinopec Shanghai Research Institute of Petrochemical Technology
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Sinopec Shanghai Research Institute of Petrochemical Technology
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B39/00—Compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites; Their preparation; After-treatment, e.g. ion-exchange or dealumination
    • C01B39/02—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof; Direct preparation thereof; Preparation thereof starting from a reaction mixture containing a crystalline zeolite of another type, or from preformed reactants; After-treatment thereof
    • C01B39/36—Pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11
    • C01B39/38—Type ZSM-5
    • C01B39/40—Type ZSM-5 using at least one organic template directing agent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86—Catalytic processes
    • B01D53/8621—Removing nitrogen compounds
    • B01D53/8625—Nitrogen oxides
    • B01D53/8628—Processes characterised by a specific catalyst
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J29/00—Catalysts comprising molecular sieves
    • B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
    • B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
    • B01J29/40—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively
    • B01J29/42—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively containing iron group metals, noble metals or copper
    • B01J29/46—Iron group metals or copper
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    • C01B39/00—Compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites; Their preparation; After-treatment, e.g. ion-exchange or dealumination
    • C01B39/02—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof; Direct preparation thereof; Preparation thereof starting from a reaction mixture containing a crystalline zeolite of another type, or from preformed reactants; After-treatment thereof
    • C01B39/06—Preparation of isomorphous zeolites characterised by measures to replace the aluminium or silicon atoms in the lattice framework by atoms of other elements, i.e. by direct or secondary synthesis
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
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    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Abstract

The invention discloses a sodium-free Fe-ZSM-5 molecular sieve, which solves the problem of large grain size of Fe-ZSM-5 molecular sieves synthesized in the prior art. The invention adopts the molecular sieve with the iron element state value of 95-99.5 percent, the molecular sieve with the b-axis size of 5-50 nm, the anisometric size ratio of 1-4 and the Na content of 0.001-0.03 wt.% SiO2/Fe2O3＝20‑200，SiO2/Al2O3The technical proposal of 20-200 solves the problems better.

Description

Sodium-free Fe-ZSM-5 molecular sieve and synthesis method thereof
Technical Field
The invention belongs to the technical field of catalytic chemistry and chemical engineering, and particularly relates to a sodium-free Fe-ZSM-5 molecular sieve and a synthesis method thereof.
Background
Nitrogen oxides (NOx) are atmospheric airOne of the main pollutants of pollution, ammonia Selective Catalytic Reduction (SCR), is widely used for NOx removal. The catalyst widely used in the past decades and commercialized is mainly a catalyst of a V-Ti system, but the catalyst has certain defects, mainly the V element has a relatively large harm to the environment. In view of this, transition metal doped molecular sieves that are relatively less toxic and less expensive have attracted considerable attention from researchers, and Fe-ZSM-5 is one of the most representative catalysts. The patent CN201610320403.3 discloses a Fe-ZSM-5 Rh and Er doped composite catalyst applied to SCR reaction, firstly preparing a Na-ZSM-5 molecular sieve with high silica-alumina ratio, and mixing the molecular sieve with NH4Exchanging Cl solution to prepare NH4-SM-5 molecular sieves, followed by NH4Adding ferric nitrate solution into the-ZSM-5 molecular sieve, preparing the Fe-ZSM-5 molecular sieve by an ion exchange method, and doping a small amount of Rh and Er by an impregnation method to prepare the composite Fe-SM-5 catalyst. Patent CN201810207118.X discloses a molecular sieve type catalyst for SCR reaction, which comprises the steps of firstly pretreating a carrier, then preparing impregnation liquid, weighing powder according to a certain proportion, adding the powder into the impregnation liquid, carrying out ultrasonic treatment for 1h, then carrying out drying and roasting treatment, and finally obtaining a metal ion/oxide modified load type Fe-ZSM-5 catalytic material, wherein the impregnation liquid comprises a Fe source, a modification component Ce source (and/or a W source, a Mo source, La and the like), silica sol, a pH regulator, a stabilizer and the like. The Fe-ZSM-5 catalyst prepared by the conventional method contains a large amount of alkali metal ions, the alkali metal ions are exchanged into ammonium radicals in one-step ammonium exchange process, the catalyst has an acidic catalytic active center after roasting, a large amount of ammonia nitrogen wastewater is generated in the ammonium exchange process, and the wastewater treatment cost is increased. Meanwhile, the Fe-ZSM-5 molecular sieve with small grain size has good diffusion performance, is beneficial to the mass transfer of reaction molecules and effectively improves the activity of the catalyst.
Disclosure of Invention
One of the technical problems to be solved by the invention is the problem that the grain size of the Fe-ZSM-5 molecular sieve synthesized in the prior art is large.
The second technical problem to be solved by the invention is that the Fe-ZSM-5 molecular sieve synthesized in the prior art contains alkali metal ions and needs an ammonium exchange process to exchange the molecular sieve into an ammonium type.
The invention aims to solve the third technical problem and provide a method for synthesizing the sodium-free Fe-ZSM-5 molecular sieve for solving the first and second technical problems.
In order to solve one of the above technical problems, the technical scheme adopted by the invention is as follows: providing a sodium-free Fe-ZSM-5 molecular sieve, wherein the iron element state value of the molecular sieve is the proportion of two peak intensities at 211nm and 245nm in an ultraviolet-visible absorption spectrum of the molecular sieve to the sum of three peak intensities at 211nm, 245nm and 280 nm; the size of the b axis of the molecular sieve is 5nm-50nm, the size ratio of the anisometric axis is 1-4, and the size ratio of the anisometric axis is the larger value of the ratio of the size of the a axis or the c axis to the size of the b axis.
To solve the second technical problem, the invention adopts the following technical scheme: providing a sodium-free Fe-ZSM-5 molecular sieve having a Na content in the molecular sieve of from 0.001 wt.% to 0.03 wt.%, preferably from 0.005 wt.% to 0.02 wt.%; SiO in molecular sieve2/Fe2O3＝20-200，SiO2/Al2O320-200; preferably SiO2/Fe2O3＝20-100，SiO2/Al2O320-100, more preferably SiO2/Fe2O3＝30-80，SiO2/Al2O3＝30-80。
In order to solve the third technical problem, the synthesis process of the sodium-free Fe-ZSM-5 molecular sieve comprises the following steps:
1) contacting a full-silicon Silicate-1 molecular sieve with an alkaline substance to obtain a mixed solution A;
2) contacting water, an iron source, an aluminum source, a silicon source, an ammonium source, an inhibitor and the mixed solution A to obtain a mixed solution B;
3) crystallizing the mixed solution B to obtain a mixed solution C;
4) and treating the mixed solution C to obtain the sodium-free Fe-ZSM-5 molecular sieve.
In order to solve the third technical problem, the synthesis process of the sodium-free Fe-ZSM-5 molecular sieve further comprises the following steps: 1) carrying out hydrothermal treatment on the mixed solution A; 2) the water, the iron source, the aluminum source, the silicon source, the guiding agent and the inhibitor are contacted for 4-12 hours at 60-80 ℃ in advance, and then the mixed solution A is added for contact to obtain a mixed solution B; 4) and (5) separating, drying and roasting the mixed solution C.
In the above technical solution, preferably, the structural formula of the base is
Figure BDA0002720838670000021
Wherein R1, R2, R3 and R4 are respectively one of ethyl, propyl or isopropyl, preferably R1, R2, R3 and R4 are all propyl; or R1 and R2 are isopropyl groups, and R3 and R4 are ethyl groups.
In the above technical solution, preferably, the concentration of the aqueous solution of the alkaline substance is 12% to 45%.
In the above technical solution, preferably, the mass ratio of the aqueous solution of the basic substance to the all-silicon Silicate-1 molecular sieve is (3-18): 1.
In the technical scheme, preferably, the hydrothermal treatment condition after the alkaline substance aqueous solution and the all-silicon Silicate-1 molecular sieve are mixed is that the mixture is subjected to sealing treatment at 85-125 ℃ for 3-20 h.
In the above technical solution, preferably, the iron source is one or more of ferric sulfate, ferric chloride or ferric nitrate.
In the above technical solution, preferably, the aluminum source is one or more of aluminum sulfate, aluminum chloride, and aluminum nitrate.
In the above technical solution, preferably, the silicon source is one or more of white carbon black, ammonium silica sol, or solid silica gel.
In the above technical solution, preferably, the ammonium source is a mixture of one or more of ammonia water and ammonium salts such as ammonium chloride, ammonium sulfate or ammonium nitrate, wherein a molar ratio of the ammonia water to the ammonium groups in the ammonium salts is 5-10.
In the above technical solution, preferably, the structural formula of the inhibitor is NH2-C6H4-(CH2)n-C6H4-NH2Wherein n is 5 to 10; more preferably, the inhibitor has the formula NH2-C6H4-(CH2)6-C6H4-NH2Or NH2-C6H4-(CH2)10-C6H4-NH2。
In the above technical solution, preferably, the mixed solution B contains water, iron source, aluminum source, ammonium source and silicon source in molar ratios of H to H as the silicon source2O/SiO26-18; the silicon source is SiO as iron source2/Fe2O350-1000; silicon source and aluminum source of SiO2/Al2O350-1000; ammonium source, silicon source is N/SiO20.2-1.0 percent of inhibitor, silicon source is Y/SiO2＝0.2-0.8。
In the above technical solution, preferably, the mixed solution a and the silicon source (as pure SiO) in the mixed solution B2Calculated) is A/SiO2＝0.35-1.1。
According to the technical scheme, preferably, the crystallization condition of the mixed liquid B is that the mixed liquid B is subjected to closed reaction for 12 to 96 hours at the temperature of between 125 and 155 ℃.
The four-coordinate iron content and the six-coordinate iron content in the molecular sieve framework are determined by the peak intensity of an ultraviolet-visible absorption spectrum, a spectrogram has two strong absorption bands of charge transition at 211nm and 245nm, the two peaks correspond to the four-coordinate iron in the framework in the molecular sieve, a shoulder exists at 280nm of the spectrogram and corresponds to the six-coordinate iron, the ultraviolet-visible absorption spectrum is tested by adopting a Perkinelmer Lambda 35 ultraviolet-visible spectrum analyzer in the United states, polytetrafluoroethylene is taken as a reference, and the wavelength range is tested: 190-500 nm. The intensities of the three peaks of 211nm, 245nm and 280nm are the peak heights of the absorption peaks corresponding to the three wavelengths of 211nm, 245nm and 280nm obtained by the measurement of the instrument.
The size of the molecular sieve is an SEM test result, the SEM adopts a Hitachi S-4800 cold field high resolution emission scanning electron microscope of Hitachi of Japan to measure, and the main technical indexes are as follows: secondary electron resolution: 1.0nm (15KV, WD is more than or equal to 4mm, 1.4nm (1KV, WD is more than or equal to 1.5mm), magnification of low magnification mode multiplied by 20 to 2000, high magnification mode multiplied by 100 to 800000, sodium content and SiO2/Fe2O3And SiO2/Al2O3For ICP test results, the solution of the test sample was measured using a Thermo IRIS Intrepid II XSP model inductively coupled plasma emission spectrometerThe solution method is as follows: 50mg of sample is added into a plastic bottle, 20g of deionized water is added, about 1.5g of hydrofluoric acid (40 wt%) is added, the mixture is kept stand for 2 hours, then 20g of deionized water is added, and after the sample is completely dissolved and no precipitate exists, the ICP test is carried out.
The state value of the iron element of the sodium-free Fe-ZSM-5 molecular sieve synthesized by the method is 95-99.5 percent, the b-axis size of the molecular sieve is 5-50 nm, the major value of the anisometric size ratio is 1-4, the Na content is 0.001-0.03 wt percent, and the SiO content is 0.001-0.03 wt percent2/Fe2O3＝20-200，SiO2/Al2O320-200. The molecular sieve does not need an ammonium exchange process before use, thereby avoiding the discharge of a large amount of ammonia nitrogen wastewater. When the molecular sieve is applied to selective reduction of nitrogen oxides by ammonia, the low-temperature catalytic activity is obviously improved. The reaction conditions are that the total flow of gas is 500ml/min, N2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The reaction temperature is 220 ℃, and the conversion rate of nitrogen oxides is 80-85%.
Drawings
FIG. 1 is a UV-VIS absorption spectrum of the Na-free Fe-ZSM-5 molecular sieve synthesized by the present invention
Detailed Description
[ example 1 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 60g of an alkaline substance aqueous solution with the mass concentration of 30% (R1, R2, R3 and R4 in an alkaline structural formula are all propyl), then treating for 5 hours in a closed environment at 110 ℃ to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.229g of ammonium chloride and 10.72g of NH2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝50、SiO2/Al2O3＝50、N/SiO2＝0.3、Y/SiO20.4 mol ratio of ammonia water to ammonium chloride of 6, mixed liquid BAnd the mass ratio of the medium mixed solution A to the white carbon black is 0.6, crystallizing the mixed solution B in a 130 ℃ closed environment for 48 hours to obtain a mixed solution C, and performing conventional separation, drying and other processes on the mixed solution C to obtain the Fe-ZSM-5 molecular sieve. The proportion of the two peak intensities at 211nm and 245nm in the ultraviolet-visible absorption spectrum of the molecular sieve to the three peak intensities at 211nm, 245nm and 280nm is 98.5%, the iron element state value of the molecular sieve is 98.5%, the b-axis size of the molecular sieve is 30nm, the a-axis size is 80nm, the c-axis size is 115nm, the anisometric size ratio is 3.8, the Na content is 0.005 wt.%, and the SiO content is higher than that of the molecular sieve2/Fe2O3＝51，SiO2/Al2O350. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 82%.
[ example 2 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 60g of 30% alkaline substance aqueous solution (R1, R2 are isopropyl groups, R3 and R4 are ethyl groups in an alkaline structural formula), treating for 5 hours in a closed environment at 110 ℃ to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.229g of ammonium chloride and 10.72g of NH2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2＝0.3、Y/SiO2The molar ratio of ammonia water to ammonium chloride is 6, the mass ratio of the mixed liquid A to the white carbon black in the mixed liquid B is 0.6, the mixed liquid B is crystallized in a 130 ℃ closed environment for 48 hours to obtain a mixed liquid C, and the mixed liquid C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The two peak intensities at 211 and 245nm in the ultraviolet-visible absorption spectrum of the molecular sieve are respectively 211 and 24The ratio of the intensities of three peaks at 5nm and 280nm is 99.0%, the iron state value of the molecular sieve is 99.0%, the b-axis size of the molecular sieve is 31nm, the a-axis size is 60nm, the c-axis size is 110nm, the magnitude of the anisometric size ratio is 3.5, the Na content is 0.002 wt.%, and the SiO content is 99.0%2/Fe2O3＝52，SiO2/Al2O352. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 81%.
[ example 3 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 60g of an alkaline substance aqueous solution with the mass concentration of 12% (in an alkaline structural formula, R1, R2, R3 and R4 are all propyl), then treating for 5 hours in a closed environment at 110 ℃ to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.229g of ammonium chloride and 10.72g of NH2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2＝0.3、Y/SiO2The molar ratio of ammonia water to ammonium chloride is 6, the mass ratio of the mixed liquid A to the white carbon black in the mixed liquid B is 0.6, the mixed liquid B is crystallized in a 130 ℃ closed environment for 48 hours to obtain a mixed liquid C, and the mixed liquid C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The proportion of the two peak intensities at 211nm and 245nm in the ultraviolet-visible absorption spectrum of the molecular sieve to the three peak intensities at 211nm, 245nm and 280nm is 95.0%, the iron element state value of the molecular sieve is 95.0%, the b-axis size of the molecular sieve is 35nm, the a-axis size is 65nm, the c-axis size is 115nm, the anisometric size ratio is 3.3, the Na content is 0.025 wt.%, and the SiO content is higher than that of the molecular sieve2/Fe2O3＝51，SiO2/Al2O350. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 80%.
[ example 4 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 60g of 45 mass% alkaline substance aqueous solution (R1, R2, R3 and R4 in an alkaline structural formula are all propyl), treating for 5 hours in a closed environment at 110 ℃ to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.229g of ammonium chloride and 10.72g of NH2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2＝0.3、Y/SiO2The molar ratio of ammonia water to ammonium chloride is 6, the mass ratio of the mixed liquid A to the white carbon black in the mixed liquid B is 0.6, the mixed liquid B is crystallized in a 130 ℃ closed environment for 48 hours to obtain a mixed liquid C, and the mixed liquid C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The proportion of two peak intensities at 211nm and 245nm in an ultraviolet-visible absorption spectrum of the molecular sieve to three peak intensities at 211nm, 245nm and 280nm is 99.5%, the iron element state value of the molecular sieve is 99.5%, the b-axis size of the molecular sieve is 32nm, the a-axis size is 72nm, the c-axis size is 105nm, the anisometric size ratio is 3.3, the Na content is 0.02 wt.%, and the SiO content is2/Fe2O3＝51，SiO2/Al2O351. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 83%.
[ example 5 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 15g of an alkaline substance aqueous solution with the mass concentration of 30% (R1, R2, R3 and R4 in an alkaline structural formula are all propyl), then treating for 5 hours in a closed environment at 110 ℃ to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.229g of ammonium chloride and 10.72g of NH2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2＝0.3、Y/SiO2The molar ratio of ammonia water to ammonium chloride is 6, the mass ratio of the mixed liquid A to the white carbon black in the mixed liquid B is 0.6, the mixed liquid B is crystallized in a 130 ℃ closed environment for 48 hours to obtain a mixed liquid C, and the mixed liquid C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The molecular sieve had an iron state value of 95.2%, a b-axis size of 30nm, an a-axis size of 33nm, a c-axis size of 56nm, a value of 1.9 for the anisometric size ratio, a Na content of 0.03 wt.%, and SiO2/Fe2O3＝52，SiO2/Al2O350. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 84%.
[ example 6 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 90g of 30% alkaline substance aqueous solution (R1, R2, R3 and R4 in the alkaline structural formula are all propyl), treating for 5 hours in a closed environment at 110 ℃ to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate and 0.968g of nitreIron (III), white carbon black (6 g), ammonia (28 wt.%), ammonium chloride (0.229 g), NH (10.72 g)2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2＝0.3、Y/SiO2The molar ratio of ammonia water to ammonium chloride is 6, the mass ratio of the mixed liquid A to the white carbon black in the mixed liquid B is 0.6, the mixed liquid B is crystallized in a 130 ℃ closed environment for 48 hours to obtain a mixed liquid C, and the mixed liquid C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The iron element state value of the molecular sieve is 99.1 percent, the b-axis size of the molecular sieve is 34nm, the a-axis size is 45nm, the c-axis size is 95nm, the anisometric size ratio is 2.8, the Na content is 0.015 wt.%, and SiO2/Fe2O3＝50，SiO2/Al2O351. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 82%.
[ example 7 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 60g of an alkaline substance aqueous solution with the mass concentration of 30% (R1, R2, R3 and R4 in an alkaline structural formula are all propyl), then treating for 20 hours in a sealed environment at 85 ℃ to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.229g of ammonium chloride and 10.72g of NH2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2＝0.3、Y/SiO20.4% of ammoniaThe mol ratio of water to ammonium chloride is 6, the mass ratio of the mixed solution A to the white carbon black in the mixed solution B is 0.6, the mixed solution B is crystallized for 48 hours in a closed environment at 130 ℃ to obtain a mixed solution C, and the mixed solution C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The iron element state value of the molecular sieve is 96.5%, the b-axis size of the molecular sieve is 31nm, the a-axis size is 67nm, the c-axis size is 110nm, the anisometric size ratio is 3.5, the Na content is 0.005 wt.%, and SiO2/Fe2O3＝51，SiO2/Al2O351. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 85%.
[ example 8 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 60g of an alkaline substance aqueous solution with the mass concentration of 30% (R1, R2, R3 and R4 in an alkaline structural formula are all propyl), then treating for 3 hours in a 125 ℃ closed environment to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.229g of ammonium chloride and 10.72g of NH2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2＝0.3、Y/SiO2The molar ratio of ammonia water to ammonium chloride is 6, the mass ratio of the mixed liquid A to the white carbon black in the mixed liquid B is 0.6, the mixed liquid B is crystallized in a 130 ℃ closed environment for 48 hours to obtain a mixed liquid C, and the mixed liquid C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The state value of iron element of the molecular sieve is 98.1%, the b-axis size of the molecular sieve is 33nm, the a-axis size is 54nm, the c-axis size is 101nm, the anisometric size ratio is 3.1, the Na content is 0.012 wt.%, and SiO2/Fe2O3＝50，SiO2/Al2O350. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 83%.
[ example 9 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 60g of an alkaline substance aqueous solution with the mass concentration of 30% (R1, R2, R3 and R4 in an alkaline structural formula are all propyl), then treating for 5 hours in a closed environment at 110 ℃ to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.283g of ammonium sulfate and 10.72g of NH2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2＝0.3、Y/SiO2The molar ratio of ammonia water to ammonium chloride is 6, the mass ratio of the mixed liquid A to the white carbon black in the mixed liquid B is 0.6, the mixed liquid B is crystallized in a 130 ℃ closed environment for 48 hours to obtain a mixed liquid C, and the mixed liquid C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The iron element state value of the molecular sieve is 97.4%, the b-axis size of the molecular sieve is 42nm, the a-axis size is 87nm, the c-axis size is 145nm, the anisometric size ratio is 3.5, the Na content is 0.022 wt.%, and SiO2/Fe2O3＝50，SiO2/Al2O349. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 80%.
[ example 10 ]
The synthesis process of the sodium-free Fe-ZSM-5 molecular sieve is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 60g of an alkaline substance aqueous solution with the mass concentration of 30% (R1, R2, R3 and R4 in an alkaline structural formula are all propyl), then treating for 5 hours in a closed environment at 110 ℃ to obtain a mixed solution A, and then mixing 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.343g of ammonium nitrate and 10.72g of NH2-C6H4-(CH2)6-C6H4-NH2Mixing with 3.6g of the mixed solution A to obtain a mixed solution B, wherein H2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2＝0.3、Y/SiO2The molar ratio of ammonia water to ammonium chloride is 6, the mass ratio of the mixed liquid A to the white carbon black in the mixed liquid B is 0.6, the mixed liquid B is crystallized in a 130 ℃ closed environment for 48 hours to obtain a mixed liquid C, and the mixed liquid C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The iron element state value of the molecular sieve is 98.5%, the b-axis size of the molecular sieve is 40nm, the a-axis size is 80nm, the c-axis size is 150nm, the anisometric size ratio is 3.8, the Na content is 0.006 wt.%, and the SiO content is 0.006 wt.%2/Fe2O3＝52，SiO2/Al2O349. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 81%.
Comparative example 1
In comparison with example 1, except that the inhibitor NH was not added2-C6H4-(CH2)6-C6H4-NH2And others are the same. The synthesis process is as follows: uniformly mixing 5g of Silicate-1 molecular sieve and 60g of 30% alkaline substance aqueous solution (R1, R2, R3 and R4 in an alkaline structural formula are all propyl groups), then treating for 5 hours in a closed environment at 110 ℃ to obtain a mixed solution A,then, 14.4g of water, 1.332g of aluminum sulfate, 0.968g of ferric nitrate, 6g of white carbon black, 3.21g of ammonia water (28 wt.%), 0.229g of ammonium chloride and 3.6g of mixed solution A are uniformly mixed to obtain mixed solution B, wherein H is2O/SiO2＝8、SiO2/Fe2O3＝200、SiO2/Al2O3＝200、N/SiO2The molar ratio of ammonia water to ammonium chloride is 6, the mass ratio of the mixed liquid A to the white carbon black in the mixed liquid B is 0.6, the mixed liquid B is crystallized in a 130 ℃ closed environment for 48 hours to obtain a mixed liquid C, and the mixed liquid C is subjected to conventional separation, drying and other processes to obtain the Fe-ZSM-5 molecular sieve. The proportion of the two peak intensities at 211nm and 245nm in the ultraviolet-visible absorption spectrum of the molecular sieve to the three peak intensities at 211nm, 245nm and 280nm is 98.5%, the iron element state value of the molecular sieve is 98.5%, the b-axis size of the molecular sieve is 70nm, the a-axis size is 120nm, the c-axis size is 320nm, the anisometric size ratio is 4.6, the Na content is 0.005 wt.%, and the SiO content is higher than that of the molecular sieve2/Fe2O3＝51，SiO2/Al2O350. The obtained molecular sieve is applied to the reaction of ammonia selective reduction of nitrogen oxide, the total flow of gas is 500ml/min, and N is2As balance gas, O2Is 5% by volume, NO and NH3The content is 500ppm, and the gas space velocity is 200000h-1The temperature was 220 ℃ and the nitrogen oxide conversion was 62%.
TABLE 1
Figure BDA0002720838670000091

Claims (14)

1. The sodium-free Fe-ZSM-5 molecular sieve is characterized in that the iron element state value in the ZSM-5 molecular sieve is 95% -99.5%, wherein the iron element state value of the ZSM-5 molecular sieve is the proportion of two peak intensities at 211nm and 245nm in an ultraviolet-visible absorption spectrum of the molecular sieve to the sum of three peak intensities at 211nm, 245nm and 280 nm.
2. The sodium-free Fe-ZSM-5 molecular sieve of claim 1, the Fe-ZSM-5 molecular sieve having a b-axis dimension of 5nm to 50nm and an iso-axis dimension ratio of greater than 1 to 4, wherein the iso-axis dimension ratio is the greater of the a-axis or the ratio of the c-axis dimension to the b-axis dimension.
3. The sodium-free Fe-ZSM-5 molecular sieve of claim 1, having a Na content in the molecular sieve of from 0.001 wt.% to 0.03 wt.%, preferably from 0.005 wt.% to 0.02 wt.%; SiO in the molecular sieve2/Fe2O3＝20-200，SiO2/Al2O320-200, preferably SiO2/Fe2O3＝20-100，SiO2/Al2O320-100, more preferably SiO2/Fe2O3＝30-80，SiO2/Al2O3＝30-80。
4. A method for synthesizing a sodium-free Fe-ZSM-5 molecular sieve is characterized by comprising the following steps:
1) contacting a full-silicon Silicate-1 molecular sieve with an alkaline substance to obtain a mixed solution A;
2) contacting water, an iron source, an aluminum source, a silicon source, an ammonium source, an inhibitor and the mixed solution A to obtain a mixed solution B;
3) crystallizing the mixed solution B to obtain a mixed solution C;
4) and treating the mixed solution C to obtain the sodium-free Fe-ZSM-5 molecular sieve.
5. The method of synthesizing a sodium-free Fe-ZSM-5 molecular sieve according to claim 4 wherein the steps further comprise: 1) carrying out hydrothermal treatment on the mixed solution A; 2) the water, the iron source, the aluminum source, the silicon source, the guiding agent and the inhibitor are contacted for 4-12 hours at 60-80 ℃ in advance, and then the mixed solution A is added for contact to obtain a mixed solution B; 4) and (5) separating, drying and roasting the mixed solution C.
6. The method of claim 4 for the synthesis of sodium free Fe-ZSM-5 molecular sieve, the alkali having the formula
Figure FDA0002720838660000011
Wherein R1, R2, R3 and R4 are respectively one of ethyl, propyl or isopropyl, preferably R1, R2, R3 and R4 are all propyl; or R1 and R2 are isopropyl groups, and R3 and R4 are ethyl groups.
7. The method for synthesizing the sodium-free Fe-ZSM-5 molecular sieve of claim 4, wherein the alkaline substance is an aqueous solution with a mass concentration of 12% -45%.
8. The method for synthesizing sodium-free Fe-ZSM-5 molecular sieve according to claim 4, wherein the mass ratio of the aqueous alkaline substance solution to the all-silicon Silicate-1 molecular sieve is (3-18): 1.
9. The method for synthesizing the Na-free Fe-ZSM-5 molecular sieve of claim 4, wherein the hydrothermal treatment condition after mixing the alkaline aqueous solution and the all-silicon Silicate-1 molecular sieve is sealing treatment at 85-125 ℃ for 3-20 h.
10. The method of synthesizing a sodium-free Fe-ZSM-5 molecular sieve according to claim 4, wherein the iron source is one or more of ferric sulfate, ferric chloride or ferric nitrate.
11. The method of synthesizing sodium-free Fe-ZSM-5 molecular sieve of claim 4, wherein the aluminum source is one or more of aluminum sulfate, aluminum chloride or aluminum nitrate; the silicon source is one or more of white carbon black, ammonium silica sol or solid silica gel; the ammonium source is a mixture of one or more of ammonia water and ammonium salts such as ammonium chloride, ammonium sulfate or ammonium nitrate, wherein the molar ratio of the ammonia water to the ammonium groups in the ammonium salts is 5-10.
12. The method of claim 4, wherein the inhibitor has the formula NH2-C6H4-(CH2)n-C6H4-NH2Wherein n is 5 to 10, preferably the inhibitor has the formula NH2-C6H4-(CH2)6-C6H4-NH2Or NH2-C6H4-(CH2)10-C6H4-NH2。
13. The method of claim 4, wherein the mixture A and the Si source (pure SiO) are present in the mixture B2Calculated) is A/SiO20.35-1.1; the crystallization condition of the mixed liquid B is that the mixed liquid B is subjected to closed reaction for 12 to 96 hours at the temperature of between 125 and 155 ℃.
14. A reaction for selectively reducing nitrogen oxide by using ammonia gas through a molecular sieve is characterized in that the sodium-free Fe-ZSM-5 molecular sieve in the claims 1-3 or the molecular sieve synthesized by the synthesis method in the claims 4-13 is adopted, and the reaction conditions are that the nitrogen oxide is contacted with the ammonia gas in the presence of the molecular sieve catalyst, wherein the total gas flow is 400-600ml/min, N is2As balance gas, O2Has a volume fraction of 4-6%, NO and NH3The content is 400-600ppm, and the gas space velocity is 100000-300000h-1The reaction temperature is 200-240 ℃.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102502696A (en) * 2011-11-16 2012-06-20 大连理工大学 Synthetic method of ZSM-5 zeolites
CN103183359A (en) * 2013-03-20 2013-07-03 中国科学院青岛生物能源与过程研究所 Nanoscale FeZSM-5 molecular sieve, and preparation method and application thereof
CN103950951A (en) * 2014-04-25 2014-07-30 清华大学 Method for synthesizing heteroatomic ZSM-5 molecular sieve and application thereof
US20170190589A1 (en) * 2014-07-28 2017-07-06 Research Institute Of Shaanxi Yanchang Petroleum (Group) Co., Ltd. One-step preparation method for hollow shell type small grain zsm-5 molecular sieve
CN108217681A (en) * 2018-01-19 2018-06-29 山东齐鲁华信高科有限公司 A kind of preparation method of the Fe-ZSM-5 molecular sieves of high Fe content

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102502696A (en) * 2011-11-16 2012-06-20 大连理工大学 Synthetic method of ZSM-5 zeolites
CN103183359A (en) * 2013-03-20 2013-07-03 中国科学院青岛生物能源与过程研究所 Nanoscale FeZSM-5 molecular sieve, and preparation method and application thereof
CN103950951A (en) * 2014-04-25 2014-07-30 清华大学 Method for synthesizing heteroatomic ZSM-5 molecular sieve and application thereof
US20170190589A1 (en) * 2014-07-28 2017-07-06 Research Institute Of Shaanxi Yanchang Petroleum (Group) Co., Ltd. One-step preparation method for hollow shell type small grain zsm-5 molecular sieve
CN108217681A (en) * 2018-01-19 2018-06-29 山东齐鲁华信高科有限公司 A kind of preparation method of the Fe-ZSM-5 molecular sieves of high Fe content
WO2019140750A1 (en) * 2018-01-19 2019-07-25 山东齐鲁华信高科有限公司 Method for preparing high-iron content fe-zsm-5 molecular sieve

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